This invention relates to a laboratory test plate having a plurality of chambers or wells and more particularly to such apparatus having a plurality of removable well strips wherein individual wells may be separated from the strips.
Multi-well test plates are used for holding a variety of test media in procedures such as cell growth, virus isolation, titration, toxicity tests, and other assays. Such plates typically include a base and cover and may further include means for separating one or more of the wells. See, for example, U.S. Pat. Nos. 4,154,795 to Thorne, 4,038,149 to Liner et al., 3,907,505 to Beall et al., and 3,649,464 to Freeman.
It has been suggested to provide a tray with a rectangular array of compartments for holding a multiplicity of individual microtest wells in U.S. Pat. No. 4,154,795 to Thorne. Each compartment is defined by four posts which engage the outer surfaces of a well disposed in the compartment. In one embodiment, all of the wells are molded integrally with one another by means of stems consisting of mold flashings so that the individual wells can be fitted into the compartments more rapidly. The stems are easily broken to enable one or more wells to be separated from each other when required. Alternatively, one or more rows of wells may be integrally connected to form a strip of wells.
The test plate described in Thorne is expensive to produce because the base tray requires an array of posts forming separate compartments for holding the wells in a fixed position. When removed from the base, the well strips tend to curve because the mold flashings cannot maintain the strip in a flat linear array. It is important that the wells be held flat, with the bottom surfaces of all wells in one plane, when taking an optical density reading through the bottom surfaces of the wells.
It has also been suggested to provide a rectangular frame having a central opening in which a plurality of separate well strips may be disposed. While the well strips may be removed from the base, the individual wells are rigidly connected such that they are not separable. The separation of individual wells is important where only some of the wells need to be subjected to further tests.
It is an object of this invention to provide a multi-well test plate which includes a plurality of removable well strips and a base.
Another object is to provide well strips which hold a plurality of wells in a fixed linear array whether or not the strips are disposed in the base.
A further object of this invention to provide such a plate wherein the wells are individually separable.
A still further object is to provide such a plate which is inexpensive to produce.